Battery for an aircraft

Abstract

A battery for an aircraft. The present embodiments further relate to an aircraft with at least one such battery. The battery may include a battery casing with a casing wall that forms an interior volume, a plurality of battery cells that is arranged in the interior volume, and a functional layer that is arranged at the casing wall between the plurality of battery cells and the battery casing. The functional layer may include an intumescent material that, in case of a breach of the battery casing, is adapted to ensuring flame containment within the interior volume and mitigation of uncontrolled heat and gas emission from the interior volume through the breach of the battery casing.

What is claimed is: 
     
       1. A battery for an aircraft, comprising:
 a battery casing with a casing wall that forms an interior volume; 
 a plurality of battery cells that is arranged in the interior volume; and 
 a functional layer that is arranged at the casing wall between the plurality of battery cells and the battery casing, wherein the functional layer comprises an intumescent material that, in case of a breach of the battery casing, is adapted to ensuring flame containment within the interior volume and mitigation of uncontrolled heat and gas emission from the interior volume through the breach of the battery casing; and 
 a structural support layer that encloses the plurality of battery cells and separates the plurality of battery cells from the functional layer, 
 wherein the functional layer further comprises: 
 a fibrous mat that comprises the intumescent material, wherein the fibrous mat remains evenly distributed in a predetermined arrangement between the structural support layer and the casing wall in case of an exposure to a temperature that is below a predetermined threshold, and wherein the fibrous mat is free to move between the structural support layer and the casing wall in case of an exposure to a temperature that is equal to or above the predetermined threshold. 
 
     
     
       2. The battery of  claim 1  wherein the plurality of battery cells comprises at least one of lithium-ion, sodium ion, or magnesium ion battery cells. 
     
     
       3. The battery of  claim 1  further comprising:
 a gas evacuation venting tube adapted to enable a controlled evacuation of gases in case of a thermal runaway of at least a portion of the plurality of battery cells. 
 
     
     
       4. The battery of  claim 1  wherein the functional layer increases in volume upon intumescence of the intumescent material by at least a factor of 3. 
     
     
       5. The battery of  claim 1  wherein the fibrous mat comprises at least one of mineral wool, glass fibers, mineral fibers, alkaline earth silica fibers, carbon fibers, basalt fibers, binder, methylol melamine, phenol-formaldehyde resin, epoxy resin, pentaerythritol, monomer, dimer, trimer, starch, dextrin, sorbitol, mannitol, expandable graphite, exfoliating graphite, or char former polymer. 
     
     
       6. The battery of  claim 1  wherein the fibrous mat is at least partially shaped in a corrugated way with a predetermined height and a predetermined distance between parallel folding lines. 
     
     
       7. The battery of  claim 6  wherein a ratio between the predetermined height and the predetermined distance is between 0.5 and 5. 
     
     
       8. The battery of  claim 6  wherein the fibrous mat is superficially cut along ridges of the parallel folding lines. 
     
     
       9. The battery of  claim 6  wherein the functional layer further comprises:
 stabilizing means for keeping the fibrous mat evenly distributed in the predetermined arrangement between the structural support layer and the casing wall in case of the exposure to the temperature that is below the predetermined threshold. 
 
     
     
       10. The battery of  claim 9  wherein the stabilizing means comprise at least one of pins, rods, or wires. 
     
     
       11. The battery of  claim 10  wherein the fibrous mat is threaded onto the at least one of pins, rods, or wires. 
     
     
       12. The battery of  claim 1  wherein the functional layer further comprises:
 an additional intumescent material that forms a coating on the casing wall. 
 
     
     
       13. An aircraft with a battery comprising:
 a battery casing with a casing wall that forms an interior volume; 
 a plurality of battery cells that is arranged in the interior volume; and 
 a functional layer that is arranged at the casing wall between the plurality of battery cells and the battery casing, wherein the functional layer comprises an intumescent material that, in case of a breach of the battery casing, is adapted to ensuring flame containment within the interior volume and mitigation of uncontrolled heat and gas emission from the interior volume through the breach of the battery casing; and 
 a structural support layer that encloses the plurality of battery cells and separates the plurality of battery cells from the functional layer, 
 wherein the functional layer further comprises: 
 a fibrous mat that comprises the intumescent material, wherein the fibrous mat remains evenly distributed in a predetermined arrangement between the structural support layer and the casing wall in case of an exposure to a temperature that is below a predetermined threshold, and wherein the fibrous mat is free to move between the structural support layer and the casing wall in case of an exposure to a temperature that is equal to or above the predetermined threshold. 
 
     
     
       14. The aircraft of  claim 13 , wherein the plurality of battery cells comprises at least one of lithium-ion, sodium-ion, or magnesium-ion battery cells. 
     
     
       15. The aircraft of  claim 13 , wherein the battery further comprises:
 a gas evacuation venting tube adapted to enable a controlled evacuation of gases in case of a thermal runaway of at least a portion of the plurality of battery cells. 
 
     
     
       16. The aircraft of  claim 13 , wherein the functional layer increases in volume upon intumescence of the intumescent material by at least a factor of 3. 
     
     
       17. The aircraft of  claim 13 , wherein the fibrous mat comprises at least one of mineral wool, glass fibers, mineral fibers, alkaline earth silica fibers, carbon fibers, basalt fibers, binder, methylol melamine, phenol-formaldehyde resin, epoxy resin, pentaerythritol, monomer, dimer, trimer, starch, dextrin, sorbitol, mannitol, expandable graphite, exfoliating graphite, or char former polymer. 
     
     
       18. The aircraft of  claim 13 , wherein the fibrous mat is at least partially shaped in a corrugated way with a predetermined height and a predetermined distance between parallel folding lines. 
     
     
       19. The aircraft of  claim 18 , wherein a ratio between the predetermined height and the predetermined distance is between 0.5 and 5. 
     
     
       20. The aircraft of  claim 18 , wherein the fibrous mat is superficially cut along ridges of the parallel folding lines.